Beware! Kudzu is Thriving in Indiana

The Indiana Department of Natural Resources, Division of Entomology and Plant Pathology is

working on a project to eradicate kudzu. What is kudzu? Kudzu is an invasive vine that was introduced to

the U.S. from Japan. In the southern U.S this vine can grow a foot per day, and can cover and out-compete

native vegetation causing serious damage to the forest ecosystem. It also has the potential to harbor

soybean pests and diseases. We are attempting to identify and speak with all land owners that have kudzu

on their property and/or are adjacent to wooded areas infested with kudzu, so that we may develop a

working relationship to ensure that this invasive species does not harm Indiana’s natural resources. If you

would like to report a kudzu site, please call 1-866-NOEXOTIC, or contact the Bloomington field office at

812-332-2241 or email kcote@dnr.in.gov. Additional information can be found at the Division of

Entomology and Plant Pathology web site, www.in.gov/dnr/entomolo. Thank you for your assistance and

cooperation with the project. If you have any questions or concerns regarding the project, please feel free to

contact the DNR.

What does kudzu look like?

Leaves: Kudzu leaves look

just like a bean leaf. A single

trifoliate leaf is comprised of

3 smaller leaflets. The leaves

and vines of young plants are

often hairy. Trifoliate leaves

can be as large as 10” inches

across. Brown leaves often

remain on the plant after the

first hard freeze but

eventually fall of vines by

mid winter.

Flowers:Flowers are

elongated and pinkish

to purple. The usually

appear in mid to late

summer.

Seeds: Kudzu has

a constricted seed

pod and the shape

of the individual

seeds can be seen

in the pod.

Kudzu can be confused with wild grape, wild cucumber and greenbriar.

However, these plants have a simple leaf, not a compound leaf comprised of 3

leaflets. There are native Indiana plants in the bean family that can look similar to

kudzu, but their leaves are usually not as large as kudzu and native plants usually do

not have the aggressive growth habit that kudzu has. Kudzu vines often cover trees

and all other vegetation creating a monotypic landscape.

Photo from Jody

Shimp Illinois DNR

Kudzu Distribution

Greenbriar Wild Grape vs. Kudzu Wild Cucumber

Photo from www.discoverlife.org Photo from www.allcreatures.org

Grape Kudzu

Kenneth Cote

Kenneth Cote

History: Kudzu was introduced into the United States in 1876 at the Philadelphia Centennial Exposition.

During the 1930’s, kudzu was promoted by the Soil Conservation Service and planted throughout the

southern United States where it was used for animal feed and erosion control. Since that time period kudzu

has invaded the forested lands of the southern US covering millions of acres. In Indiana Kudzu is found

primarily south of I-70, but isolated sites have been found as far north as LaPorte, Starke, and Elkhart

counties. Kudzu continues to spread further north and adapt to colder climates and is now known to

reproduce from seed in the state. As of 2-7-08, over 100 sites in 35 counties have been located in Indiana.

Damage: Kudzu out competes native vegetation by shading and using valuable nutrients. It also weighs

down trees and increases snow load on trees causing their tops to break. In addition causing tree damage,

kudzu mats can be 5 feet deep and impassible leaving many areas unusable for outdoor recreation. Kudzu

mats create an ideal environment for rodents and snakes. Finally, kudzu may act as a reservoir for

soybean diseases such as soybean rust.

Uses: In some areas of the country, kudzu vines are used for basket making and as a forage crop for

animals. There are also recipes available for making kudzu dishes, including kudzu jelly. However, in

most cases the benefits from kudzu do not out weight the negative effects it has on the environment.

Control Strategies:

Biological Control: Currently biological control of kudzu is not a practical option in the United

States. There has been a great deal of researched conducted on biological control of kudzu and

numerous fungi, bacteria, and insect biocontrol agents of kudzu are being investigated. The

bacteria Psuedomonas syringae pv Phaseolicola has been shown to kill young kudzu seedlings. A

fungus called Synchytrium puerariae has been found in Asia and California and is

Photo Courtesy of Melinda Johnson

being investigated as a potential biocontrol agent. The fungus Myrothecium verrucaria shows the

most promise. Researchers discovered that this fungi will cause provide 95-100% control of

kudzu 14 days after applications. Although this pathogen is native to the US, it will infect

soybeans. Numerous insects native to China including sawflies, borers, weevils and scarabs are

also being studied. However, all of the control agents studied are harmful to leguminous crops

such as soybeans.

Goats as Biocontrol Agents: Goats prefer broad leaf plants over grasses and have been used to

control multiflora rose and kudzu in pastures. However, the number of goats needed to provide control

may be cost prohibitive and maintaining animals at a site is labor intensive. There are also additional

problems such as erosion which can occur with over grazing and high amount of foot traffic from hooves

animals. More research needs to be conducted on this topic, but it may provide an alternative for land

owners that have animal resources available and are looking for alternative ways to control kudzu.

Mechanical: Mechanical control should be incorporated with chemical control strategies to achieve

adequate kudzu suppression. Pruning kudzu away from adjacent trees is a good way to start

controlling a kudzu patch.

• Fire: Fire alone will not control kudzu patches, but it may be used to increase accessibility

prior to chemical applications. It can also be useful for stimulating kudzu seed germination

before applying follow up herbicide applications. Check your local ordinances before

proceeding with this strategy.

• Mowing: Repeated close mowing can slow the spread of kudzu. However it can often be

difficult to get mowing equipment into rough areas. It must be performed frequently or it will

merely increase kudzu propagules resulting in more kudzu plants. All equipment should be

cleaned of plant debris before it is moved from the site.

• Heavy Machinery: In some cases, landowners have used bull dozers to remove kudzu

and reclaim land. Results from this practice can be variable. Roots are very deep in older

patches and may not be easily removed. If all of the roots are not removed, kudzu will

quickly grow back in the area. After removal, there is usually a large amount of kudzu debris

that must be disposed in a proper manner in order to prevent further spread of the plant.

Movement of heavy equipment an area results in soil compaction and can lead to a change in

the plant species that will be able to grow in a particular site.

Chemical: Results can vary between sites even with the same type of herbicide application.

Herbicide selectivity is different for each product. Some products are highly toxic to desirable tree

species unless applied in a selective manner. Product choice should consider the proximity of

water to the patch, the timing of the application, the density and age of the patch, the soil type and

the type of application method that is going to be used. All of these factors will have an effect

herbicide application results. Generally, the best time to perform foliar applications of herbicides

to kudzu is during late summer. Plants are storing carbohydrates at this time in the growing

season and are more likely to translocate herbicides to storage organs, thus providing better

control. However, dormant applications of certain herbicides have been very effective with the

proper application techniques.

Examples of Chemicals Labeled for Kudzu Control

• Banvel (Dicamba) Non-Selective

• Crossbow- 2,4 D and Triclopyr

• Escort (Metsulfuron methyl)

• Garlon 3A and Garlon 4A (Triclopyr): Non-Selective. Safety near water varies

with formulation. Dormant cut stump applications have been effective at many sites.

• Oust-Sulfometoron methyl

• Round-Up, Rodeo (Glyphosate): Non-Selective. Safer near water.

• Spike 80 DF (Tebuthiuron) Non-Selective

• Tordon (Picloram and 2,4,D) Non-Selective

• Transline (Clopyralid)- Specific to legumes, but may also stress plants in

Compositae family.

• Veteran 720 (Dicamba and 2,4,D) Non-Selective

Pesticide information collected from:

Purdue University Fact Sheet updated 9/04,

Clemson University Fact Sheet updated 5/03

Alabama Extension Service Fact Sheet, Revised 1999.

Mention of Trade Name implies no endorsement of a single product or associated

company. Always read pesticide labels before making any pesticide application. Label

information can be obtained from suppliers, or on the web at www.cdms.net and

www.greenbook.net. For a complete list of registered products contact the Office of

the Indiana State Chemist.

Should I mow or cut the kudzu before or after chemical applications? The

answer is no. Do not mow or cut the kudzu before or after chemical applications. Allow the

kudzu to grow until treatment. A higher the leaf to root ration will likely increase the chances of

herbicides translocating to the root system where they can ensure adequate suppression.

Performing cut stump herbicide applications to large vines growing up trees may reduce the

volume of foliar herbicide needed for coverage and reduce pesticide drift by eliminating spraying

high in the tree tops.

Alternative species and Erosion control: In many cases, native vegetation will recolonize a site

once the kudzu is removed. However, this may not be true for sites with poor soil conditions or where soil

erosion occurs. A soil erosion plan should be implemented at these sites and an alternative, non invasive,

non allelopathic plants species should be used to hold the soil until native vegetation can become

established. Contact your local soil conservation district for assistance with erosion control and

replacement species.

Written By Kenneth W. Cote, Nursery Inspector, Indiana DNR, Division of Entomology and Plant

Pathology, 2005. Photographs Courtesy of Jody Shimp from the Illinois DNR and Melinda Johnson an

Indiana Resident. Updated February 2008.

References

Abbas H. K., Johnson B. B., Shier W.T., Tak H, Jarvis B.B. and Boyette C. D. 2002 Phytotoxicity and

mammalian cytotoxicity of macrocyclic trichothecene mycotoxins from Myrothecium verrucaria.

Phytochemistry 59 (3) P. 309-313.

Abbas H. K., Tak H., Boyetter C.D., Shier W. T., and Jarvis B.B. 2001. Macrocylic trichothecenes are

undetectable in kudzu (pueraria Montana) plants treated with a high –producing isolate of Myrothecium

verrucaria. Phytochemistry 58(2) p. 269-276

Beer Brian, Bredenkamp, Christry. 2001. Controlling kudzu in Western North Carolina. North

Carolina Cooperative Extension Service, Division of Livestock and Division of Horticulture.

Case Study for Regional Perspectives in Ecology and Environmental Science. Submitted by Dr. Brian

Shmaefsky, Kingwood College: Location: Sohterastern. Title: Harvesting Kudzu; A Controversial

Business.

Hipkins P. L. 1988. Control of kudzu during the dormant season. Proceedings, Southern Weed Science

Society. 51 p. 191-192

Miller, James H . 1988. Kudzu Eradication with New Herbicides. Proceedings, Southern Weed Science

Society 41 p. 220-225.

Mississippi Agricultural and Forestry Experiment Station. Date unknown. Effective Kudzu Control.

Mississippi State University Cooperative Extension Service.

Longwell Tim, Miller, Nich and Schreiweis, Melissa. Date Unknown. Weed Control and Fire Hazard

Reducition in Forest Ecosystems with Sheep Grazing.

Luginbuh J.M., Greene J.M., Poore M.H. and Mueller J.P. 1996. Use of goats as biological control

agents for the control of unwanted vegetation. Web Search in 3-04.

Van Drieshce R. et al. 2002. Biological Control of Invasive Plants in the Eastern United States. USDA

Forest Service Publication. 413pp.